public class Circle2 {
   private double radius = 1;
   private static int numberOfObject = 0;
  public Circle2() {
     numberOfObject ++;
    }
   public Circle2(double newRadius){
       radius = newRadius;
       numberOfObject ++;
   }
 public double getRadius(){
     return radius;
 
    }
     public void setRadius(double newRadius) {
        radius = (newRadius >= 0 ? newRadius : 0);
     }
     public static int getNumberOfObject(){
         return numberOfObject;
    }
     public double getArea(){
         return radius * radius * Math.PI;
    }
 }

